Need help with illustrator

[B5ECF]

So I wanted to make a pattern brush with the yellow image but when I make the brush it turns grey when I draw strokes. I checked for Greystoke setting but my colour settings are cmyk. And then when I try to change the colour it does as pictured above, anyone have any solutions to fixing this?

[sishamIAGD]

When you create the brush make sure the 'Colorization' is set to none. See below...